COMPARING THE BENDING STIFFNESS OF DOMESTIC AND IMPORTED PINUS-ELLIOTTII RADIUS EDGE DECKING

Radius edge decking (RED) produced from both domestic and tropically g rown Pinus elliottii was evaluated with respect to growth characterist ics and bending stiffness. Imported and domestic Pinus elliottii RED s amples were selected by a Southern Pine Inspection Bureau quality supe rvisor to be similar in growth and defect characteristics. The modulus of elasticity (MOE) in bending of 5/4- by 6-inch Standard grade RED w as determined by applying a single point load to the testing specimens with the grade-controlling defect of each piece centered under the lo ad in the middle of the 24-inch span. Correlations between rings per i nch and MOE and percent summerwood and MOE were investigated. Best-fit distributions for MOE were determined using the Graphical Distributio n Analysis (GDA) software package. The imported Pinus elliottii was fo und to have significantly lower average values of rings per inch, perc ent summerwood, and MOE than the domestic elliottii. Percent summerwoo d was found to be correlated with MOE for both samples. Distributional differences were also found between the imported and domestic materia l for the properties of percent summerwood and MOE.